The dog owner said her Chihuahua disappeared days before Christmas. She went around the neighborhood hanging signs looking for Meryl.

According to a Port St. Lucie police report, Mills was staying at the victim's house and admitted to choking Meryl, breaking the dog's windpipe because "he urinated on the bed while he was sleeping over."

Mills told the victim it was an accident and said he left Meryl along a canal bank near Castinet Avenue.

Police searched the area and found bones.

Mills returned to the victim's house to hang out with her son Jan. 12, police said. The son said he heard a dog scream and yelp while Mills was in the living room.

The police report said Mills threw Fluffy against the wall and then "threw her body over the backyard fence."

Through a series of Facebook and text messages, Mills admitted to killing the dogs, police said.

The victim, who didn't want to be identified, said she did not think he was capable of killing anyone or anything.

"I had notified shelters," she said. "I called animal control. I had everybody, including Gavin, who actually assisted me with going to neighbors' houses and looking for my dog."

She said it's been a horrifying experience.

"It's a shame, because I was helping this kid out," she said. "I mean, who would have thought he would injure any of my animals?"

Mills is charged with two counts of animal cruelty and possession of a weapon by a convicted felon.